From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Thu, 4 Mar 2021 10:36:21 +0000 (+0000)
Subject: xen/dmop: Fix XEN_DMOP_nr_vcpus to actually return data
X-Git-Tag: 4.15.0-rc3~24
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=6b0ac9a4e239d00d5e07f0313903b88b08d39452;p=people%2Ftklengyel%2Fxen.git

xen/dmop: Fix XEN_DMOP_nr_vcpus to actually return data

The const_op boolean needs clobbering to cause data to be written back to the
caller.

Fixes: c4441ab1f1 ("dmop: Add XEN_DMOP_nr_vcpus")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
---

diff --git a/xen/arch/arm/dm.c b/xen/arch/arm/dm.c
index d689e336fd..1b3fd6bc7d 100644
--- a/xen/arch/arm/dm.c
+++ b/xen/arch/arm/dm.c
@@ -128,6 +128,7 @@ int dm_op(const struct dmop_args *op_args)
         struct xen_dm_op_nr_vcpus *data = &op.u.nr_vcpus;
 
         data->vcpus = d->max_vcpus;
+        const_op = false;
         rc = 0;
         break;
     }
diff --git a/xen/arch/x86/hvm/dm.c b/xen/arch/x86/hvm/dm.c
index f4f0910463..b60b9f3364 100644
--- a/xen/arch/x86/hvm/dm.c
+++ b/xen/arch/x86/hvm/dm.c
@@ -612,6 +612,7 @@ int dm_op(const struct dmop_args *op_args)
         struct xen_dm_op_nr_vcpus *data = &op.u.nr_vcpus;
 
         data->vcpus = d->max_vcpus;
+        const_op = false;
         rc = 0;
         break;
     }